Skip to content

Creating a back adjusted continuous price series from log returns

3 messages · Wolfgang Wu, Whit Armstrong, Patrick Burns

#
I am trying to create a continuous daily futures contract time series. I've already calculated the log returns for this series and want to create an artificial price series starting with the most recent price (the one with the latest date).
Basically I am trying to create a price series with the following logic:

p(-1) := exp(ln(p(0)) - r)

I have got p(T) and the log return series r and am trying to create the price series.

with
p(0) = todays price
p(-1) = yesterdays price
p(T) = the price at time T (current available price)
r = log return between yesterdays price and todays price

Thanks

Wolfgang Wu

__________________________________________________
Do You Yahoo!?
Sie sind Spam leid? Yahoo! Mail verf?gt ?ber einen herausragenden Schutz gegen Massenmails.
#
I was interpreting the question as looking for:

price.vector <- original.price * exp(cumsum(return.vector))


Patrick Burns
patrick at burns-stat.com
+44 (0)20 8525 0696
http://www.burns-stat.com
(home of "The R Inferno" and "A Guide for the Unwilling S User")
Whit Armstrong wrote: